Invasive biosensors, such as sensors for wearable monitoring devices, include thin sensor wires or electrodes that are insertable into a patient's skin. Sensing circuitry reads biological information about the patient via the thin wires. To use some devices, patients or medical professionals are required to connect the sensor wires to the sensing circuitry. For example, the sensor wires may be implanted into the patient's skin during a first step, and, during a second step, the sensor wires may be connected to a monitoring device. This two-step approach may be overly complicated for some patients to perform on their own and/or may be cost prohibitive to have a medical professional perform. In addition, such devices may include multiple openings by which wires and the sensing circuitry may be exposed to potential moisture that may significantly impact performance of the biosensor.
Preassembling the sensor wires within the monitoring device is a possibility. For example, proximate portions of the sensor wires can be soldered or welded to a printed circuit board within the monitoring device. Exposure of the sensor wires to such high localized temperatures associated with soldering and welding, however, may damage the sensor wires; especially, if the sensor wires have been coated with a membrane. Additionally, such approaches may result in sensor wires that are unsuitably rigid as a result of the soldering and/or welding.
In addition to the considerations above, the size of the monitoring device is a practical consideration for wearable devices. To accommodate the required sensing circuitry, power source, and the like to process the biological information, wearable monitoring devices may include multiple parts that are coupled together to form working devices. Not only does the use of multiple parts cause the devices to be bulky, but it also creates multiple areas for possible moisture ingress (e.g., seals between parts).